PB1940: ACQUIRED APLASTIC ANEMIA: THE CHALLENGE OF TREATMENT IN MEXICO. SINGLE HEMATOLOGY CENTER EXPERIENCE
Authors: M. L. Guajardo Leal, G. Sotomayor Duque, A. J. Mecott Estudillo, D. Cruz Contreras, M. P. Pequeño Luevano, H. P. Sorkee Dávila, J. A. Carrizales Villarreal, J. L. Cedillo, S. Baltazar, R. E. De León Cantú, R. Hernandez Valadez, I. Borjón Cabada, C. Quirino Marquez, J. D. Garza Escobar, Y. B. García Cerda, W. Nava Gutiérrez, D. C. Aldama Gutiérrez, L. G. Ávila Contreras, V. Valeugarín, K. M. Machuca Adame, L. O. Gudiño Cobos
Journal: HemaSphere (2022)

Background: Aplastic anemia is a T-cell mediated autoimmune pathology that results in apoptosis of CD34 + progenitor cells, resulting in pancytopenia. In Mexico, most patients receive first-line immunosuppressive treatment, the international literature reports a response of 94% and survival rates of 97%. Aims: Establish the outcomes to immunosuppressive treatment (IST) and hematopoietic stem cell transplant (HSCT) in patients with aplastic anemia in our center. Methods: Observational, retrospective, cross-sectional and analytical. Patients with Aplastic Anemia, older than 16 years, from January 2014 to December 2020. We analyze the data with absolute frequencies, percentages and measures of central tendency. The qualitative variables were analyzed with chi squared and the quantitative variables Student’s T. Survival was analyzed with Kaplan-Meier curves. The statistical package SPSS version 21.0 will be used. Results: We include 36 patients, 23 patients (64%) was male and female 13 patients (36%) with median age of 46 years (17-84) and median follow-up of 28.6 months (4.8-80.1). Classification by degree of severity were: Non severe 9 patients (25%), severe 13 patients (36%), and very severe 14 patients (38%). Response Rates: The first-line therapy was cyclosporine (CsA) mono therapy in 52.7%, CsA and rabbit thymoglobulin (rATG) in 38.8% and CsA/danazole in 8.3%. Four patients (11.1%) achieved a complete response, 2 patients with CsA, 1 with rATG and 1 with CsA/danazole and partial response in eight patients (22%). Global response was 32%. After 6 months of treatment, those patients who did not achieve a response and without rATG in the first-line who were unable to undergo a HSCT were given a course of rATG of second line therapy (11 patients). Four patients (36.3%) achieved a partial response and two patients (18.1%) with a complete response. Two patients started with second-line danazol (5.5%), one patient obtained a partial response. A total of 10 patients (27.7%) underwent a HCST achieving a response a partial responsen in 30% and complete response in 50%. Survival and mortality: Overall survival (OS) at 3, 4, and 5 years was 45%, 30%, and 24% respectively. Patients who achieved a response had a 4-year OS of 47% versus 17% for those who did not achieve a response (p = 0.001). Patients who underwent HSCT had a 4-year overall survival of 45% with a median post-transplant survival of 20.7 months. Compartive results of patients with >40 years old vs < 40 years old in OS was 75 % vs 35% at 18 months. The principal cause of death was infection (27%). Image:Summary/Conclusion: The IST has a lower response rate in our center compared to what has been published internationally. Transplantation continues to be the gold standard treatment, especially in patients under 40 years of age, so it is important to procure an HLA donor in this group of patients and to do without delay.